Identification On Sensitivity Of Different Human Cells Against Human Parvovirus B19

Human Parvovirus B19(referred to as B19 virus) is a representative of erythrovirus, parvovirus family. B19 virus mainly transmits through respiratory tract in public places, and the infected population spreads universally around the world, including adults and children of diverse nationalities in different countries and regions as reported. As studies in recent years showed, the spectrum of clinical B19 virus infection is broad, and B19 virus particles can be observed at lesions such as fetal liver, kidney, placenta vascular endothelial cells in the electron microscope. B19 virus can also transmit through channels like blood and blood substitutes, infant vertical infection. etc. For this reason, more and more attention has been paid to and studies been carried out on B19 virus over the past few years. B19 virus mainly combines with globoside(Gb4) on the cell surface, which is basically found on the surface of erythroid progenitor cells in bone marrow.In spite of the broad spectrum of clinical B19 virus infection, no cell line has ever been found available to B19 virus infection. At the current stage, B19 virus can not be in vitro isolated and cultured, and high-viral-load virus still depends on sources like infected plasma/serum.Object:To identify the sensitivities of different cell lines of human origin including K562, HL-60, THP-1, Jukat and Huh715 cell to B19 virus, with the semi-permissive cell UT-7 / EPO as a reference.Methods:First, got and cultured UT-7 / EPO cell line semi-permissive to B19 virus, adjusted the cell state and explored the optimal conditions of culture. Screened infected plasma with a viral load greater than 107 copies/mL and did typing, selected the most epidemic virus I as the source of infection. Then infected different human cells with infected plasma, extracted randomly cell supernatants and DNA, RNA(cDNA reverse) in the cells at 2h, 8h, 16 h, 24 h, 32 h, 40 h, 2d, 3d, 4d, 5d, 6d respectively for quantitative PCR testing. In the end, performed Western Blot and immunofluorescence(IF) testing for the cells with sensitivity comparable to or better than the semi-permissive cell UT-7/EPO according to the results of quantitative PCR testing.Results:Testing for the infected cell supernatants evidenced that, B19 virus can be adsorbed on the surface of the semi-permissive cell UT-7/EPO, whose trend of change prevails over those of other cells; testing for DNA and RNA in the cells evidenced that, UT-7/EPO cell is sensitive to B19 virus in a certain extent, but its transcription and replication are inactive, and the basic B19 virus fails to enter into other cells; Western Blot and immunofluorescence(IF) testing for UT-7/EPO cell showed that, a certain amount of protein shells can be produced but cannot encapsulate the said cell to form virus seeds of the corresponding amount.Conclusion:This study makes clear the system of UT-7/EPO cell semi-permissive to B19 virus being infected with B19 virus, and the efficiency of infection of the said cell and the condition of progeny virus seed production. The sensitivities of the other five leukemia cells and liver cancer cells of human origin to B19 virus are far lower than that of UT-7/EPO cell, presenting that B19 virus has a high efficiency of infection and a broad spectrum of infection even in the human body, but is restricted by many factors in the process of in vitro reproduction. Exploring and seeking cell lines sensitive to B19 virus is of great significance to studies on the replication cycle of B19 virus in cells, intracellular oxidative stress and endoplasmic reticulum stress, RNA transcription profiles and other functional mechanisms.